Dockerfile: install byacc

Install byacc required to build cst from source.

Signed-off-by: Leonard Anderweit <l.anderweit@phytec.de>
diff --git a/tools/docker/Dockerfile b/tools/docker/Dockerfile
index b99796a..80bc2a9 100644
--- a/tools/docker/Dockerfile
+++ b/tools/docker/Dockerfile
@@ -64,6 +64,7 @@
 	binutils-dev \
 	bison \
 	build-essential \
+	byacc \
 	cgpt \
 	clang-18 \
 	coreutils \